The status register labelled SR contains four flag bits that give information about the state of the CPU. There are three flags that indicate whether a calculation overflowed, gave a negative result or gave a zero result. Calculations set these flags
S The sign flag indicates a negative result.
O The overflow flag indicates overflows.
Z The zero flag indicates a zero result.
I Interrupts enabled. STI turns this on. CLI turns this off.
These flags are described in more detail later.
JMP Rep
This command causes the central processing unit (CPU) to jump back and repeat earlier commands or jump forward and skip some commands.
